The present invention relates to an endotracheal aspiration probe for a patient under artificial ventilation.
It is known that a patient under artificial ventilation is connected to an artificial respiration apparatus by way of a ventilation tube placed in his trachea and supplied with respiratory gas by said apparatus. Such a patient secretes pulmonary mucus which requires to be eliminated several times a day. Probes are also already known for aspirating this pulmonary mucus. Depending on the design of the ventilation tube, such a probe can be introduced into the trachea either as a replacement for said ventilation tube, or through the latter, and the artificial ventilation must either be interrupted or, by contrast, can be maintained during aspiration of the mucus.
However, even in the most favorable case in which the artificial ventilation is maintained during the aspiration of the mucus, there are not inconsiderable risks of the patient suffering hypoxia, which can cause the heart to slow down, or even arrest, and these risks are due to the fact that an artificial respirator insufflates respiratory gas only about one third of the time. Thus, during the other two thirds of the time, the aspiration of the pulmonary mucus can lead to pulmonary collapse.
The object of the present invention is to completely eliminate the risks of hypoxia during aspiration of pulmonary mucus from a patient under artificial ventilation.
To this end, according to the invention, the endotracheal aspiration probe for aspirating pulmonary mucus from a patient under artificial ventilation, connected to an artificial respiration apparatus by way of a ventilation tube placed in his trachea, said aspiration probe being intended to be connected to aspiration means and to be introduced into said ventilation tube, is distinguished by the fact that it includes a channel for permanent blowing of a respiratory gas under pressure, and that the distal orifice of said blowing channel is lateral and sufficiently distant from the distal end of said probe to be situated opposite the inner wall of said ventilation tube, even when said probe occupies its position of maximum insertion inside said ventilation tube.
Thus, during aspiration of the pulmonary mucus, respiratory gas is insufflated into the patient""s trachea so that a pulmonary collapse cannot take place. Moreover, because the distal orifice of the blowing channel is situated opposite the inner wall of the ventilation tube, this blown gas cannot damage the tracheal and bronchial mucous membranes.
To achieve this result, it is advantageous, in the case of an adult, for the distance between the distal orifice of the blowing channel and the distal end of the aspiration probe to be equal to at least 10 cm, and preferably at least approximately equal to 15 cm. If the probe is intended for a young child, this distance can be at least equal to 2 cm.
It is advantageous to provide, in said aspiration probe, a channel which is used for measuring pulmonary pressure and opens out in the vicinity of the distal end of the aspiration probe, and to use the pressure in said channel for measuring pressure in order to adjust the flow rate of the respiratory gas so as to prevent pulmonary collapse.
The gas being blown can be oxygen, for example.
In an advantageous embodiment, the blowing channel and/or the channel for measuring pressure are formed in the wall of said aspiration probe.
Advantageously, the pressure of the respiratory gas being blown is chosen at most equal to 3.5 bar, while the under pressure at the distal end of the aspiration probe is of the order of several hundreds of millibars.
The figures in the attached drawing will show clearly how the invention can be realized. In these figures, identical references designate similar elements.